〔Abstract〕 Objective To explore the therapeutic value of different treatment methods under endoscopy for larger (diameter greater than 20 mm) large bowel laterally spreading tumors (LST). Methods From January 2015 to January 2020, 17 cases of endoscopic pre-cut mucosal resection pre-cut (EMR), 11 cases of endoscopic piecemeal mucosal resection (EPMR) and 35 cases of endoscopic submucosal resection (ESD) were performed in Ningde Hospital Affiliated to Ningde Normal University. A retrospective study was conducted on these cases. They were set into pre-cut EMR group, EPMR group, and ESD group to compare the operation time, resection rate, complications and recurrence rate. Results The operation time of ESD group was significantly longer than that of EMR group and EPMR group, the difference was statistically significant (P < 0.05). The block removal rates of pre-incision EMR group and ESD group were 94.1% and 97.1%, respectively, with no statistical significance (P > 0.05). The cured resection rate in ESD group was significantly higher than that in EPMR group, and the difference was statistically significant (P < 0.05), but there was no significant difference between ESD group and EMR group (P > 0.05). The incidence of surgical complications in pre-cut EMR group, EPMR group and ESD group was 17.6%, 18.2% (2/11) and 5.7% (2/35), respectively. The incidence of postoperative complications in ESD group was lower than that in pre-cut EMR group and EPMR group, but the difference was not statistically significant (P > 0.05). Conclusion Compared with EPMR, ESD and pre-cut EMR have a better clinical effect in the treatment of large intestine LST, which can improve the en bloc resection rate and the cure resection rate of the lesion, and reduce the risk of postoperative complications. They can be used as the preferred treatment method for LST of large intestine larger than 20 mm.